Scree plot. Scree plot using Johnston County Osteoarthritis Project radiographic data. Based on the eigenvalue (the dashed line indicates an eigenvalue of 1.0) and scree plot criteria, a three-, four-, or five-factor solution would be acceptable. Subjective examination based on interpretability and simple structure led the authors to use a four-factor solution.
Nelson et al. Arthritis Research & Therapy 2011 13:R176 doi:10.1186/ar3501